U.S. President Donald Trump has threatened to use emergency powers to bypass Congress and end Government shutdown as well as to pay for a wall on the U.S.-Mexico border.

Trump flew to the Texas border with Mexico to try to bolster his case for the border wall as a partial U.S. government shutdown tied to the issue stretched into its 20th day with no sign of new talks to resolve the impasse.

“We can declare a national emergency. We shouldn’t have to,” Trump told reporters. “This is just common sense.”

Trump said his lawyers had told him he had the power to invoke national emergency powers to get his wall funded.

“I have the absolute right to declare a national emergency,” Trump told reporters at the White House. “I’m not prepared to do that yet, but if I have to, I will.”

Such a step would likely prompt an immediate legal challenge over constitutional powers from congressional Democrats – a challenge Trump said he would win.

The Republican president is adamant that a government funding bill to end the shutdown include $5.7 billion for a border barrier – his signature campaign promise. Congressional Democrats oppose that.

The standoff has left a quarter of the federal government closed down and hundreds of thousands of federal employees without pay.

A day after he stormed out of a meeting with Democratic leaders, Trump attacked them for refusing his demand, calling them harder to deal with than China, a rival power.

“I find China, frankly, in many ways to be far more honorable than Crying Chuck and Nancy. I really do,” Trump said, referring to House of Representatives Speaker Nancy Pelosi and Senate Democratic leader Chuck Schumer.

The House passed two bills to fund the departments of transportation, housing and agriculture – each drawing a few more Republican votes than a similar effort on Wednesday to reopen the Treasury Department and other agencies.

The White House has said Trump would veto the bills if they made it to his desk.